Forming of articles by rolling

ABSTRACT

This invention relates to rolling elongated bars between a backed-up forming roller and die means. The die means is preferably formed by a pair of rollers which most conveniently roll T-section bar. The die means may alternatively be a long die. Containment means is provided to prevent the die means bursting outwardly during rolling.

United States Patent [191 Marcovitch 1 FORMING OF ARTICLES BY ROLLING[21] Appl. No.: 185,333

Related U.S. Application Data [63] Continuation of Ser. No. 889,627,Dec. 31, 1969,

' abandoned.

[30] Foreign Application Priority Data June 18, 1969 South Africa69/4340 Feb. 14, 1966 South Africa 66/804 [52] U.S. CL 72/199, 72/177,72/241, 72/224 [51] Int. Cl B2lb 1/08 [58] Field of Search 72/225, 177,199, 179., 72/224, 241, 242; 29/1495 C [56] I References Cited UNITEDSTATES PATENTS 1,856,269 5/1932 Schultz et a1. 72/224 .[451 May 7,1974

Primary Examiner-Milton S. Mehr Attorney, Agent, or Firm-Young &Thompson [5 7] ABSTRACT This invention relates to rolling elongated barsbetween a backed-up forming roller and die means. The

2 Claims, 8 Drawing Figures 1 FORMING OF ARTICLES BY ROLLING This is acontinuation, of application Ser. No. 889,627, filed Dec. 3l, 1969, andnow abandoned.

This invention relates to apparatus for forming metal articles byrolling.

According to this invention there is provided apparatus for formingended metal articles by rolling, comprising a forming roll, back-uprolls on which the forming roll is rotatably mounted, and die means; thedie means and the forming roll being formed with cooperating surfacemeans one of which defines a recess and the other of which fits closelyinto the recess and defines therewith a working space in which aworkpiece may be shaped by. the two surface means. Preferablycontainment means is provided to act on the sides of the roll or diemeans in which the recess is formed to balance outward forces during theforming operation.

The die means may be formed as an elongated die or may be comprised byone or two or more die rolls. The die means is conveniently also backedup and the recess or surface means is preferably formed in the diemeans. The containment means may also be in the form of additionalback-up rolls where the die means comprises the roll or rolls.Alternatively the containment means may comprise a plurality of jacks,which where the die means comprises a roll or rolls are arranged on theaxis of the roll or rolls. I

When the die means is formed as a pair of rolls these may be arrangedwith their axes slightly inclined to one another, and may be spacedapart so that the recess formed thereby has 'no base.

When the die means is formed as a roll or rolls,a bending roll may beprovided adjacent the die means continuously to bend the formedworkpiece.

When the die means comprises an elongated die, the forming roll and itsback-rolls may conveniently be mounted on a bracket which is movable ona back-up surface relative to the preferably stationary die.

Embodiments of the invention will now be described by way of examplewith reference to the accompanying drawings.

SHORT DESCRIPTION OF DRAWINGS In the drawings:

FIG. 1 is a section through apparatus for rolling T section bar, thesection being taken on line 1 l of FIG. 2;

FIG. 2 is a side view of the apparatus of FIG. 1;

FIG. 3 is a side view of the apparatus for rolling chanin the form of apair of die rolls 12.

The forming roll 11 has an enlarged central portion 14 with acylindrical working surface, and a pair of stout stub axles 15. Theforming roll 11 is engaged by a back-up roll 16 of substantially greaterdiameter than the central portion 14 and having a recess 16a toaccommodate the central portion 14. The axial length of contact betweenthe stub axles 15 and the back-up rolls 16 is substantially greater thanthe axial length of the central portion 14 of the roll 11.

The die rolls 12 are arranged with their axes 17 inclined by a verysmall angle to one another and intersecting approximately mid-way alongthe length of the central portion 14, of the forming roll 11. The dierolls 12 are mounted on axles 18 carried in bearings 19 in the apparatushousing (indicated generally at 21).

Each roll 12 comprises a head portion 22 and a flange protion 23. Thehead portion 22 has a frustoconical rolling surface 24 which tapers toits outer end where it is provided with a domed top portion 25 having afrustoconical edge 26 which lies at right angles to the rolling surface24. The front face 27 of the flange portion 23 is also frustoconical andlies parallel to the frustoconical edge 26 of the domed portion 25 ofthe head portion 22. The cone angles of surfaces 24, 26 and 27, theinclination of the die axes 17 and the disposition of the rolls 14 issuch that (i) the parts of the surfaces 24 opposite the forming roll 11are aligned and are parallel to the surface of the working surface ofthe central portion 14 of the forming roll 11, (ii) the front faces 27of the flange portions 23 are spacedapart by nel section bar, thesection being taken on line 3 3 FIGS. 1 AND 2 Referring now to FIGS. 1and 2, the apparatus there shown'is the currently preferred embodimentof the invention. The apparatus is adapted to roll a T section the axiallength of the forming roll 11 and closely receive part of the formingroll 11, therein, and (iii) the frustoconical edge portions 23 arespaced from one another.

The working surface of the portion 14 and the surfaces 24, 25 and 27form a rolling recess in which a workpiece or stock is rolled. As thedie rolls 12 are spaced apart the rolling recess is without a base forthe space in which the leg 31 of the T section bar 10 is formed.

A pair of back-up rolls 28 having their axes at right angles to the axes17 respectively are provided adjacent the location of the forming roll1 1. These back-up rolls 28 are of substantial diameter and act on therear face '35 of the flange portion 23 of the die rolls 12 to supportrolls it is bent by the roll 34 into the appropriate arcuate shape witheither the cross-piece or leg of the T innermost;

It will be seen that as the forming roll 11 is backed up by the largeback-up rolls 16 and as the flange portions 23 of the die rolls 12 areheld against bursting by the containment means, it is possible to act onthe workpiece 10 with extremely high pressures acting on the part of theworkpiece passing through the throat. These pressures may be of theorder of one hundred and fifty tons per square inch or more. Thisenables a workpiece to be cold rolled into a T section in a minimum ofpasses and, in particular, normally in one pass.

It is also possible to produce a highly polished and accuratelydimensioned T section with a relativelylong .central leg 31 from roughrectangular section stock or workpieces 32 billets 32.

It will also be appreciated that as the bar is ended,

i.e., it is not endless as, for example, a ring, the rolling recess iscircumferentially wholly bounded and any reduction of the cross-sectionof the workpiece as compared to that of the stock 32 is compensated forby the elongation of the workpiece.

It must be pointed out, however, that due to the side entrapment andhigh intensities of pressure used, a large reduction in one pass isobtained as well as filling of all details. of the die space.

It is further pointed out that the severe side entrapment encouragesfilling of the die space and reduces tendency for the bar to enlongateinstead of filling this die space.

FIGS. 3 AND 4 Apparatus for rolling channel section, ended bars 41 isshownin- FIGS. 3 and 4. This apparatus comprises a main forming roll 42and die means in the form of-a single die roll 43. The forming roll 42has an enlarged central portion 44 having a profiled working surfaceformed with a pair of steps 44a. The form roll 42 also has a pair ofstout stub axles 45. The stub axles 45 are each engaged by a pair ofback-up rolls 46 of substantially greater diameter than the centralportion 44. The axial length of contact between the stub axles 45 andthe back-up rolls 46 is substantially greater than the axial length ofthe central portion 44 of the roll 42.

The die roll 43 is arranged with its axis 47 parallel to the axis 48 ofthe roll 42 and is supported over its entire length by a pair of back-uprolls 49. An annular recess 51 is formed in the die roll 43. Theenlarged central portion 44 of the forming roll 42 closely fits therecess 51 and the surfaces of the recess and the portion 44 define arolling recess in which a rough, generally rectangular section workpiece52 is cold rolled into a polished bar 41 of the desired and accuratesection.

In order to pre-stress the die roll 43 and to prevent it bursting'underthe-rolling forces a pair of hydraulic cylinders 54 are providedarranged with their axes aligned with the axis 47 of the roll 43 andcarrying enlargements 55 at the ends of their piston rods 56. Theseenlargements 55, which can be in the form of pads, act

on the ends of the roll 43 and serve as containment means therefor. Thepiston rods may rotate with the roll 43 during operation of theapparatus. Alternatively the enlargements 55 may be rotatably mounted onthe ends of the piston rods 56.

This apparatus will operate at pressures of the same order as thosementioned above for cold rolling the workpiece and as in the firstdescribed embodiment, a bending roller 57 may be provided to formarcuate bars 58, with the base of the channel section either inside oroutside.

FIGS. 5 AND 6 In the apparatus shown in these Figures, the die means isin the form of an elongated, rigid fixed die 61 in the upper surface ofwhich there is formed a rectan gular section recess 62. A forming roll63 has an enlarged central portion 64 which has a profiled centralworking surface with side steps 64a and which closely fits the recess 62so that the surfaces of the portion 64 and the recess 62 define aforming recess. Stout stub axles 65 project from the ends of the roll 63and are supported by a pair of back-up rolls 66 which are ofsubstantially greater diameter than the roll 63. The back-up rolls 66are carried on a shaft 66a in a bracket 67 which is slidable on theunderside of a rigid guide frame 68. The axial length of the contactbetween the stub axles 65 and the back-up rolls 66 is substantiallygreater than the axial length of the central portion 64 of the roll 63.

The side walls of the recess 62 would preferably be in the form ofinserts resting against tapered wedges which may be withdrawn to releasethe workpiece from the die 61. Other ejection means may however be usedfor extracting the workpiece- In use, rough, rectangular section, coldstock 69 is inserted in the recess 62 in the die 61. The bracket 67 iscaused to move along the frame 68 and the roll 63 cold rolls the stock69 to form channel section bar 71. If desired the rolling can take placein a number of passes and the frame 68 moved towards the die 61 betweeneach pass.

Here again the pressure intensities of the forming roll 63 on theworkpiece 69 are of the order mentioned above. a

The die 61 is usually sufficiently strong to accommodate burstingforces. However, clamps (not shown) may be provided at spaced locationsalong the die 61 acting on the sides 72 of the die 61 to prestress it inorder to enable it to withstand the immense bursting stresses imposedduring the rolling operation.

It should be noted that where the axial length of the raised portion 64of the forming roll 63 becomes long, it may be desirable to back up thisportion 64 also with a complementarily shaped back-up roll. In anyevent, the backed up length of the roll 63 should always be in excess ofthe axial length of the portion 64.

FIG. 7

In this figure there is shown a detail of the forming roller 73 and die74 used in the apparatus of FIGS. 6 and 7 to produce T section bar 75.The forming roller 73 has a cylindrical central protion 76 of enlargeddiameter. This portion 76 fits closely into the mouth of the'die-reeess77.

With this arrangement it is possible to convert by cold rollingrectangular stock into T section bar 75, which may typically be 2 inchesX I inch and of 0.040 inch wall thickness.

The forming roll may alternatively be supplemented with other formingrolls and/or carried as shown in and described with reference to FIGS.19 and 20 of my co pending application Ser. No. 615,613 filed Feb. 13,1967.

FIG. 8

The apparatus shown in FIG. 8 is used for cold rolling T sectionworkpieces and is similar to the apparatus of FIGS. 1 and 2 save thatinstead of using external die rolls 12, internal die rolls 81 areemployed.

These die rolls 81 are of large diameter and are arranged with theiraxes 81a inclined at a large angle to each other. The forming roll 82 isreceived within the rolls 81 and are backed up by back-up rolls 8 3rolling on stub axles 84 projecting from the central portion 85 of theforming roll 82. The central portion of 85 of the forming roll 82 fitsclosely into the recess formed by the GENERAL By fitting the formingroll closely into the die recess, the workpiece can be very accuratelyshaped by the die means and forming roll with no material overflow.

, The rolling operations could also take place with the metal hot orwarm.

frustoconical working faces 86, 87 and 88 of the die The rolling of theworkpiece is preferably carried out at a speed of the order of onehundred feet per minute to prevent undue scoring of the sides of the dierecess by the sides of the enlarged central portions of the rollers.However this speed is determined by the hardness and other properties ofthematerials used for these parts and may be greater or less as the casemay be.

The invention is not limited to the precise constructional detailshereinbefore described and illustrated in the drawings. Thus for examplein the FlGS. l and 2, FIGS. 3 and 4 and FIG. 7 embodiments the die rollmay be made up of three rolls bolted together. Similarly the die 61 maybe made of three rectangular plates members bolted together.

I claim:

1. Apparatus for forming metal articles by rolling,

comprising a forming roll .having working surface means, back-up rollson which the forming roll is rotatably mounted, a die roll formed with aperipheral recess having working surface means, the forming roll fittingclosely into the recess and defining therewith a working space in whicha workpiece may be shaped by the two working surface means, andcontainment means comprised by a plurality of jacks provided withpressure pads acting on the end faces of said die roll.

2. Apparatus for forming metal channels by rolling from bar stock,comprising a forming roll having a working surface characterized by anenlarged central portion having a cylindrical peripheral surfaceterminating in first side surfaces substantially perpendicular to theaxis of the forming roll, said forming roll having a pair of surfacesextending outwardly from said first side surfaces and terminating insecond side surfaces substantially perpendicular to the axis of theforming roll, back-up rolls on which the forming roll is rotatablymounted in line contact, and a die roll having a peripheral recesscomplementary in shape to, but larger than, said enlarged centralportion and in which said enlarged central portion is disposed, saidperipheral recess being bounded endwise by end walls substantiallyperpendicular to the axis of the die roll and spaced apart a distance toreceive said second side surfaces closely therebetween, whereby saidforming roll and die define between them a rolling recess in which barstock may be cold rolled to a channel of the desired and accurate CI'OSSsection.

1. Apparatus for forming metal articles by rolling, comprising a formingroll having working surface means, back-up rolls on which the formingroll is rotatably mounted, a die roll formed with a peripheral recesshaving working surface means, the forming roll fitting closely into therecess and defining therewith a working space in which a workpiece maybe shaped by the two working surface means, and containment meanscomprised by a plurality of jacks providEd with pressure pads acting onthe end faces of said die roll.
 2. Apparatus for forming metal channelsby rolling from bar stock, comprising a forming roll having a workingsurface characterized by an enlarged central portion having acylindrical peripheral surface terminating in first side surfacessubstantially perpendicular to the axis of the forming roll, saidforming roll having a pair of surfaces extending outwardly from saidfirst side surfaces and terminating in second side surfacessubstantially perpendicular to the axis of the forming roll, back-uprolls on which the forming roll is rotatably mounted in line contact,and a die roll having a peripheral recess complementary in shape to, butlarger than, said enlarged central portion and in which said enlargedcentral portion is disposed, said peripheral recess being boundedendwise by end walls substantially perpendicular to the axis of the dieroll and spaced apart a distance to receive said second side surfacesclosely therebetween, whereby said forming roll and die define betweenthem a rolling recess in which bar stock may be cold rolled to a channelof the desired and accurate cross section.